Do shorter cranks help with grumpy knees?

[T-Crush]

So as I get older, the knees are aging too (duh). Less fun going up/down multiple flights of stairs and an occasional ache that will likely result in some work down the road. My question to the forum is until that day comes, have any of you gone to shorter cranks and has it helped enough to make it worth it?

[saab2000]

What are you using now? I've not had creaky knees but I did go from 175 to 172.5 a few years ago and like it.

The short answer is probably yes, you'll like it but I guess it would depend somewhat on what you're using now. Nothing wrong with 170s.

[Hindmost]

I have had similar knee issues and I've shortened my cranks over the years. I'm no expert, I think the effect that we want is a change to the knee flexion angle.

[RFC]

Have any of you old guys with sore knees tried Glucosamine? Works very well for some people. It did for me.

Also, regular leg weight training helps to build up muscle and hold things together.

[Johnnysmooth]

No knee problems (except when something isn't adjusted just rt - eg saddle height :crap:) kept with 175 but do go with 52/36 in front and what a difference for those hills that only seem to get steeper w age

[T-Crush]

And yes to the supplement question as well. Glucosamine worked enough to notice a difference, added Shark Cartilage which seemed to boost the effects, but tried Tummeric (alone) and it worked even better still.

I'm running compacts, and it sounds like it's worth a cheap set of 172.5s to see if it helps.

[Brian Smith]

So as I get older, the knees are aging too (duh). Less fun going up/down multiple flights of stairs and an occasional ache that will likely result in some work down the road. My question to the forum is until that day comes, have any of you gone to shorter cranks and has it helped enough to make it worth it?

Clarify your question.
It seems to me that the "worth it" hurdle that shorter cranks need to clear is their cost and installation. No physician is going to prescribe them, however they may prescribe many things, none of which is less expensive than shorter cranks. Get real for us. Shorter cranks won't make you (nor your knees) younger. Are you doing something on your bike that precludes the use of shorter cranks? In these days of "road" derailers and cassettes which reach 34t as factory recommended ranges, what do you possibly give up with shorter cranks, maybe your 5 stroke sprint? Why not buy some and try them out?

[kingpin75s]

I believe yes.

I run a mix of 170 and 175mm cranks and now only run the 175s on bikes where I want to specifically keep my CG low (Eurocross & old school 26ers etc).

Happy with the change to 170mm and do notice the difference with the dirt, distance and elevation I get to ride. As a side, I also notice Q-factor. 150mm and 156mm is a big difference to me and a no go for endurance gravel. So different people have their own tolerance levels. Mine are tight. YMMV.

Happy enough with the change to 170mm that I have started to collect a few crank sets in the 160 to 167.5mm range for testing.

[T-Crush]

Fair enough. To clarify, I'm 6' 4" and overweight (working on that, which I know will help the knees substantially). I have a stable of road bikes, so a wholesale change will easily cost enough to buy a nice used titanium frame, my preference for Campy 10 Ultra-Torgue cranks doesn't make this any cheaper to consider on a permanent basis.

A complicating fact is to get home I have to ascend a 1/4 mile section that ranges from 13% to 17%, no going around. Compact has become a way of life and when Campy brought out a cassette with a 30t granny, I rejoiced out loud. As it stands, on good days I can coax myself up the hill in 34 x 30 without much protest from the knees, on bad days I toss on the trunk rack and shuttle to the bottom and back up again when done. Sprint? Not a concern. I've thought about a triple, but really, really don't like that option. It's truly a last resort.

I have one bike that's shimano equipped, and trolling ebay for a used set of Energy Compacts in something shorter than 175 for a test is the likely first step.

[Brian Smith]

Fair enough. To clarify, I'm 6' 4" and overweight (working on that, which I know will help the knees substantially). I have a stable of road bikes, so a wholesale change will easily cost enough to buy a nice used titanium frame, my preference for Campy 10 Ultra-Torgue cranks doesn't make this any cheaper to consider on a permanent basis.

A complicating fact is to get home I have to ascend a 1/4 mile section that ranges from 13% to 17%, no going around. Compact has become a way of life and when Campy brought out a cassette with a 30t granny, I rejoiced out loud. As it stands, on good days I can coax myself up the hill in 34 x 30 without much protest from the knees, on bad days I toss on the trunk rack and shuttle to the bottom and back up again when done. Sprint? Not a concern. I've thought about a triple, but really, really don't like that option. It's truly a last resort.

I have one bike that's shimano equipped, and trolling ebay for a used set of Energy Compacts in something shorter than 175 for a test is the likely first step.

Thanks for clarifying.
I can understand not wanting to convert a fleet of bikes to a shorter length crank without first knowing that it will improve the symptom you're facing.
I can also understand not wanting to make one's self content with a triple, if you don't want one.
You're considering, it seems, a non-Campag crank in your ebay pursuits, so that makes me wonder - have you considered the recent double cranks with lower than typical "compact" 34-50 ranges, such as those from Sugino? There are others out there now, too, with the proliferation of gravel bikes.
The reason I ask, is that if the gear range, to the low side, is what's stopping you, on some days, from riding that finishing climb, then it's pretty unlikely, in my opinion, that a mild crank length change is going to alleviate the knee pain. What you're after is a combination of gear ratio, road gradient, rider fitness, and rider weight that allows you a cadence that your knees and your cardiopulmonary system can deliver. Gearing down so that you can keep up 75-95rpm without sending you above your thresholds will probably help with that more than reducing joint angles a few degrees at the extremes with shorter cranks would help.
Stated another way, if a 34-50 Campag Ultra Torque crank in 172.5mm or 170mm not being likely to solve knee pain issues for you on grinding climbs is bad news, then I'm part of the bad news camp. I'd guess that would translate as "not worth it." That said, having a bike set up that allows you to make those climbs without injuring yourself would give you a common scenario to burn a bunch of calories. 13%-17% is steep, although 1/4 mile isn't so long that calories expended there are more important than the rest of a 40-mile ride. There's something to be said for using the components on your bike you like to use, and there's something to be said for not using the car to get home from a ride. Perhaps try a super low geared double crank on one bike and see how you go. People have been known to maintain a "Sunday bike" with the less practical but cool-looking stuff on it, and other bikes meant for general training and/or competition.